Top 7 questions to ask when considering additive manufacturing

Complexity, size and quantity of parts play a key role.

Comments Off on Top 7 questions to ask when considering additive manufacturing September 26, 2011
by Vincent Laithier

25 years after Chuck Hull, the founder of SLA, built the first Stereo Lithography (SL) Apparatus in 1986, Additive Manufacturing (AM) — the process which uses rapid prototyping technology to manufacture usable parts on a large scale — is becoming a reality. Rapid prototyping has certainly come a long way since the days of “don’t touch that prototype, it might break!”

R&D in advanced materials and larger, faster machines, as well as economies of scale have contributed to the advancement of AM. The past five years have seen significant consolidation of the industry: Mom and Pop shops have bowed out to firms with more capacity and materials, while companies like Stratasys and 3D Systems have vertically integrated themselves.

This is a clear indication that the industry is in the shakeout stage and has caused a shift in the way the engineers, industrial designers, or product development managers now approach product development and manufacturing. The use of Additive Manufacturing is a viable manufacturing solution, but when and how to leverage it best remains a grey area for many.

When faced with the problem of whether or not to use additive technology to fabricate a product, you have to ask the following questions:

1. How complex is the part geometry? Is it simple or does it have many undercuts and complex features? The more complex a part, the more advantageous AM becomes. In fact, AM allows to build parts that are impossible to mold or to machine and will circumvent expensive Computer Numerically Controlled (CNC) programming or tooling costs.

2. How large is the part? AM materials remain a significant cost driver. The larger the part to manufacture, the less attractive AM becomes. However, the smaller the part, the more AM becomes a cost effective solution. Smaller parts are more conducive to AM.

3. How many parts will we need? AM order quantities typically range between 10 and 1000 parts. Building more than this may not make economic sense. However, if the part is extremely complex or parts are to be delivered on a Just In Time (JIT) basis in small quantities, AM may still work. Boeing uses Laser Sintering (LS) technology to manufacturing certain parts, “If our customers purchase 40 or 50 aircraft a year, and Boeing has to make only three or four cooling ducts per aircraft, it doesn’t make sense to spend the time or money producing expensive tooling and performing the multiple layup steps,” Says Jerry Clark, Manager of the Air Vehicle Configuration Design, Integration and Rapid Development Department of The Boeing Company in Mesa.

4. How probable are design changes going forward? With AM, one can make design changes on the fly without incurring expensive costs to re-machine the current mold, or worse, remaking the mold altogether. There are no tooling or molding costs associated with AM.

5. Is this a standard part or a fully customizable part? A major benefit of AM is that custom parts can be easily made without incurring mold costs or expensive CNC machine programming costs for each individual part. The prosthesis industry is now using USP and ISO-certified RP/AM materials to manufacture prosthetic limbs, which cuts down patient wait times and costs.

6. Is there an Additive Material that will work well and last long enough for the parts intended purpose? Material development with respect to RP and AM has greatly evolved in the last 25 years. There are now hundreds of different types of RP and AM materials, all with different technical specifications, available over a slew of different processes and platforms. Consulting with a knowledgeable firm providing numerous RP and AM services will help guide you as to which process and materials to use.

7. How quickly do you need the parts? Companies providing AM services can deliver functional parts in as little as 24 hours! One no longer has to wait for tooling to obtain quality parts. Companies sometimes use AM to bridge the gap between prototype parts and production parts.

While these questions may seem simple, a closer look reveals that many of them are interdependent. Furthermore, different scenarios will change the weight each question has allocated to it. For example, manufacturing may have many fairly large and geometrically simple parts to make, which would point to other forms of manufacturing. However, sales staff may have planned meetings only days away with vital customers who cannot wait or reschedule. The company’s only option now becomes AM.

In essence, it is important to go through these questions carefully when evaluating AM as a possible manufacturing solution in order to leverage its use in a way that will help your company cut costs and development time and get your product to market faster than competitors.

Vincent Laithier is the sales manager for Montreal-based Axis Prototypes (www.axisproto.com), a full-service rapid prototyping and additive manufacturing service bureau with Canada’s largest installation of 3D Printing technologies including SLA, SLS, and Objet.